Ceiling-embedded type air conditioner, and a control method thereof

ABSTRACT

A ceiling embedded type air conditioner is embedded in a ceiling surface and includes an outlet that blows out air conditioned air toward an indoor space, and a louver capable of changing a blow-out vertical direction of the air conditioned air at the outlet. If a state in which a wind direction position of the louver is set so that it is oriented to a wind direction position continues for a first prescribed time or longer, then the louver is temporarily changed to a wind direction position more downward than the wind direction position, and once again changed to the wind direction position.

CROSS-REFERENCE TO RELATED APPLICATIONS

This U.S. National stage application claims priority under 35 U.S.C.§119(a) to Japanese Patent Application No. 2004-017197, filed in Japanon Jan. 26, 2004 the entire contents of which are hereby incorporatedherein by reference.

FIELD OF THE INVENTION

The present invention relates to an air conditioner, and a controlmethod thereof, and more particularly relates to a ceiling embedded typeair conditioner, and a control method thereof, embedded in a ceilingsurface and comprising an outlet that blows out air conditioned airtoward an indoor space, wherein the outlet comprises a guiding meanscapable of changing the vertical direction of the air conditioned airthat is blown out.

BACKGROUND ART

In a conventional ceiling embedded type air conditioner, which isdisposed so that it is embedded in a ceiling surface, an outlet thatblows out air conditioned air toward the indoor space is provided with alouver, which serves as a guiding means capable of changing the blow-outvertical direction of the air conditioned air. Furthermore, the blow-outvertical direction of the air conditioned air is changed to uniformizethe temperature distribution of the indoor space, thereby achieving asatisfactory airflow distribution of the indoor space by executingcontrol, such as: continuously swinging the louver to continuouslychange the blow-out vertical direction of the air conditioned air to thevertical direction; setting the louver so that the blow-out verticaldirection of the air conditioned air is downward during heatingoperation; or setting the louver so that the blow-out vertical directionof the air conditioned air is in the vicinity of substantially thehorizontal direction with respect to the ceiling surface (hereinafter,referred to as the horizontal blow-out state) during cooling operation.

If the louver is set to the horizontal blow-out state, then the airconditioned air blown out from the outlet flows so that it clings to theceiling surface due to the Coanda effect; consequently, even if thelouver is changed so that the air conditioned air transitions slightlydownward from the ceiling surface clinging state, there is a problem inthat the flow of the air conditioned air clinging to the ceiling surfacecannot be detached from the ceiling surface, and the blow-out verticaldirection of the air conditioned air therefore cannot be changed.Furthermore, there is a problem in that the ceiling surface tends tobecome stained in places because microgranular dust contained in the airconditioned air blown out from the outlet adheres to the ceilingsurface.

In contrast, when changing the louver to another wind direction position(hereinafter, referred to as the target wind direction position),control is executed to downwardly adjust the blow-out vertical directionof the air conditioned air by changing the blow-out vertical directionto a wind direction position that was adjusted to a position moredownward than the target wind direction position, thereby detaching fromthe ceiling surface the flow of the air conditioned air clinging to theceiling surface due to the Coanda effect, and enabling the blow-outvertical direction of the air conditioned air to be changed. Inaddition, if the air volume of the air conditioned air is small, then awide adjustment range is set for the wind direction position at thistime (i.e., so that the blow-out vertical direction of the airconditioned air transitions more downwardly) so that a feeling of adraft is not imparted to the room occupants (see, for example, JapanesePatent Publication No. 2003-269776).

SUMMARY OF THE INVENTION

Incidentally, events such as the opening and closing of doors andwindows, room occupants walking around, and the like, may affect theairflow distribution of the air conditioned space. Furthermore, if thelouver is set to the horizontal blow-out state, the abovementionedevents may disturb the airflow distribution of the air conditioned spaceand may cause the unfortunate effect wherein the flow of the airconditioned air blown out from the outlet clings to the ceiling(hereinafter, referred to as the ceiling airflow clinging effect).

However, with the abovementioned ceiling embedded type air conditioner,the blow-out vertical direction is changed to a wind direction positionthat was adjusted to a position more downward than the target winddirection position only when changing the louver to another verticalposition; therefore, the abovementioned ceiling airflow clinging effect,which might arise even in the state wherein the wind direction positionof the louver is fixed, cannot be prevented. Consequently, there stillremains the problem in that the ceiling surface tends to become stainedin places because microgranular dust contained in the air conditionedair blown out from the outlet adheres to the ceiling surface.

In addition, with the abovementioned ceiling air conditioner, the winddirection position of the louver is unfortunately changed to a winddirection position that was adjusted to a position more downward thanthe target wind direction position; as a result, the wind directionposition is set more downward than the wind direction position set bythe user, and the wind direction position set by the user, i.e., theblow-out vertical direction of the air conditioned air, cannot bemaintained. Moreover, if the air volume decreases, then the winddirection position is further adjusted downward and unfortunatelyfurther deviates from the wind direction position set by the user underoperating conditions wherein the air volume is small.

It is an object of the present invention to prevent, with a ceilingembedded type air conditioner, the unfortunate clinging to the ceilingsurface of the flow of the air conditioned air blown out from the outletdue to disturbances to the airflow distribution of the air conditionedspace, such as the opening of doors and windows.

A ceiling embedded type air conditioner according to a first aspect ofthe present invention is a ceiling embedded type air conditionerembedded in a ceiling surface, and comprising an outlet that blows outair conditioned air toward an indoor space, and a guiding means that canchange the blow-out vertical direction of the air conditioned air at theoutlet, wherein if a state, wherein the guiding means is set so that theblow-out vertical direction of the air conditioned air is oriented to afirst blow-out direction, continues for a first prescribed time orlonger, then the blow-out vertical direction of the air conditioned airis temporarily changed so that it is blown out toward a second blow-outdirection more downward than the first blow-out direction, and theblow-out vertical direction of the air conditioned air is once againchanged so that it blows out in the first blow-out direction.

With this ceiling embedded type air conditioner, if the state, whereinthe guiding means provided at the outlet is set so that the blow-outvertical direction of the air conditioned air is the first blow-outdirection, continues for the first prescribed time or longer, then theblow-out vertical direction of the air conditioned air is changed sothat the blow-out vertical direction of the air conditioned air is blownout toward the second blow-out direction more downward than the firstblow-out direction; consequently, even if the flow of the airconditioned air blown out from the outlet unfortunately clings to theceiling due to disturbances to the airflow distribution of the airconditioned space, such as the opening of a door or window, it ispossible to detach that flow from the ceiling surface. Thereby, it ispossible to reduce the time spent in the state wherein the flow of theair conditioned air blown out from the outlet clings to the ceiling, andto reduce staining of the ceiling surface.

Moreover, because the change in the blow-out vertical direction of theair conditioned air to the second blow-out direction is temporary, theblow-out vertical direction of the air conditioned air is changed fromthe first blow-out direction to the second blow-out direction, andsubsequently returned once again so that it blows out toward the firstblow-out direction, the blow-out vertical direction of the airconditioned air can be maximally maintained in the first blow-outdirection set by the user.

A ceiling embedded type air conditioner according to a second aspect ofthe present invention is a ceiling embedded type air conditioner asrecited in the first aspect of the present invention, wherein when theblow-out vertical direction of the air conditioned air is temporarilychanged by the guiding means from the first blow-out direction to thesecond blow-out direction, the air volume of the air conditioned air istemporarily changed, in a state wherein the guiding means is set so thatthe blow-out vertical direction of the air conditioned air is orientedto the first blow-out direction, from a first air volume to a second airvolume smaller than the first air volume; and when the blow-out verticaldirection of the air conditioned air is changed by the guiding meansonce again from the second blow-out direction to the first blow-outdirection, the air volume of the air conditioned air changes once againfrom the second air volume to the first air volume.

With this ceiling embedded type air conditioner, when the blow-outvertical direction of the air conditioned air is temporarily changedfrom the first blow-out direction to the second blow-out direction andthen changed once again to the first blow-out direction, i.e., when theblow-out vertical direction of the air conditioned air is temporarilyset downward, the air volume of the air conditioned air is temporarilyreduced from the first air volume to the second air volume, andconsequently a feeling of a draft is not imparted to the room occupants.

A ceiling embedded type air conditioner according to a third aspect ofthe present invention is a ceiling embedded type air conditioner asrecited in the second aspect of the present invention, wherein when asecond prescribed time has elapsed after an instruction has been givento change the air volume of the air conditioned air from the first airvolume to the second air volume, the guiding means changes the blow-outvertical direction of the air conditioned air from the first blow-outdirection to the second blow-out direction.

With this ceiling embedded type air conditioner, prior to the guidingmeans changing the blow-out vertical direction of the air conditionedair from the first blow-out direction to the second blow-out direction,an instruction is executed to change the air volume of the airconditioned air from the first air volume to the second air volume, andwaiting for the elapse of just the second prescribed time can at leastbegin to reduce the air volume, and it is therefore possible to reliablynot impart a feeling of a draft to the room occupants.

A ceiling embedded type air conditioner according to a fourth aspect ofthe present invention is a ceiling embedded type air conditioner asrecited in the third aspect of the present invention, wherein after theblow-out vertical direction of the air conditioned air has been changedby the guiding means from the second blow-out direction to the firstblow-out direction, the air volume of the air conditioned air changesfrom the second air volume to the first air volume.

With this ceiling embedded type air conditioner, after the guiding meanshas returned the blow-out vertical direction of the air conditioned airfrom the second blow-out direction to the first blow-out direction, itreturns the air volume of the air conditioned air from the second airvolume to the first air volume, and it is therefore possible to reliablynot impart a feeling of a draft to the room occupants.

A ceiling embedded type air conditioner according to a fifth aspect ofthe present invention is a ceiling embedded type air conditioner asrecited in any one of the first through fourth aspects of the presentinvention, wherein the first blow-out direction is a directioncorresponding to the upper limit at which the guiding means can changethe blow-out vertical direction of the air conditioned air blown outfrom the outlet to the indoor space.

With this ceiling embedded type air conditioner, because the firstblow-out direction is a direction corresponding to the upper limit bywhich the blow-out vertical direction of the air conditioned air can bechanged, it is possible to reduce the time spent in the state whereinthe flow of the air conditioned air blown out from the outlet clings tothe ceiling under the conditions that most easily produce the phenomenonwherein the flow of the air conditioned air blown out from the outletclings to the ceiling surface due to disturbances to the airflowdistribution of the air conditioned space, such as the opening of a dooror a window, and staining of the ceiling surface can thereby be reduced.

A ceiling embedded type air conditioner according to a sixth aspect ofthe present invention is a ceiling embedded type air conditioner asrecited in any one of the first through fifth aspects of the presentinvention, wherein the second blow-out direction is a directioncorresponding to the lower limit at which the guiding means can changethe blow-out vertical direction of the air conditioned air blown outfrom the outlet to the indoor space.

With this ceiling embedded type air conditioner, the second blow-outdirection is the direction corresponding to the lower limit by which theblow-out vertical direction of the air conditioned air can be changed,and, even if the flow of the air conditioned air blown out from theoutlet clings to the ceiling surface due to disturbances to the airflowdistribution of the air conditioned space, such as the opening of a dooror a window, the flow can be reliably detached from the ceiling surface.

A ceiling embedded type air conditioner according to a seventh aspect ofthe present invention is a ceiling embedded type air conditioner asrecited in any one of the second through sixth aspects of the presentinvention, wherein the second air volume is an air volume correspondingto the lower limit of the variable air volume range of the airconditioned air.

With this ceiling embedded type air conditioner, the second air volumeis an air volume that corresponds to the lower limit of the variable airvolume range of the air conditioned air, and, when the blow-out verticaldirection of the air conditioned air has changed downward, it ispossible to sufficiently reduce the air volume and reliably not impart afeeling of a draft to the room occupants. Here, the lower limit of thevariable air volume range of the air conditioned air means the lowerlimit of the air volume that can be set by the user, or the lower limitof the air volume at which the fan, and the like, can operate in orderto ventilate the air conditioned air contained in the ceiling embeddedtype air conditioner.

A ceiling embedded type air conditioner according to an eighth aspect ofthe present invention is a ceiling embedded type air conditioner asrecited in any one of the first through the seventh aspects of thepresent invention, wherein if an instruction is given to change theblow-out vertical direction of the air conditioned air to a thirdblow-out direction during the time when the blow-out vertical directionof the air conditioned air is temporarily changed by the guiding meansfrom the first blow-out direction to the second blow-out direction anduntil it is once again changed to the first blow-out direction, then,after the guiding means has temporarily changed the blow-out verticaldirection of the air conditioned air from the first blow-out directionto the second blow-out direction, it changes to the third blow-outdirection without changing to first blow-out direction.

With this ceiling embedded type air conditioner, even if an instructionis issued to change the setting of the blow-out vertical direction ofthe air conditioned air during the time up to when the guiding meanstemporarily changes the blow-out vertical direction of the airconditioned air from the first blow-out direction to the second blow-outdirection and then changes it once again to the first blow-outdirection, it goes through the process of changing it from the firstblow-out direction to the second blow-out direction, and consequently,even if the flow of the air conditioned air blown out from the outletclings to the ceiling due to disturbances to the airflow distribution ofthe air conditioned space, such as the opening of a door or a window, itis possible to reliably detach that flow from the ceiling surface.

Moreover, because it directly changes to the third blow-out direction,which is the target direction in changing the setting of the blow-outvertical direction of the air conditioned air, without returning fromthe second blow-out direction to the first blow-out direction, it ispossible to improve the responsiveness to changing the setting of theblow-out vertical direction of the air conditioned air.

A ceiling embedded type air conditioner according to a ninth aspect ofthe present invention is a ceiling embedded type air conditioner asrecited in any one of the second invention through seventh aspects ofthe present invention, wherein if an instruction is given to change theair volume of the air conditioned air to a third air volume during thetime when the blow-out vertical direction of the air conditioned air istemporarily changed by the guiding means from the first blow-outdirection to the second blow-out direction and until it is once againchanged to the first blow-out direction, then, after the guiding meanshas changed the blow-out vertical direction from the second blow-outdirection to the first blow-out direction, it changes the air volume ofair conditioned air to the third air volume without changing it from thesecond air volume to the first air volume.

With this ceiling embedded type air conditioner, even if an instructionis issued to change the setting of the air flow of the air conditionedair during the time up to when the guiding means temporarily changes theblow-out vertical direction of the air conditioned air from the firstblow-out direction to the second blow-out direction and then changes itonce again to the first blow-out direction, it goes through the processof changing it from the first air flow to the second air flow, andconsequently it is possible to reliably not impart a feeling of a draftto the room occupants.

Moreover, because it directly changes to the third air flow, which isthe target volume in changing the setting of the air flow of the airconditioned air, without returning from the second air flow to the firstair flow, it is possible to improve the responsiveness to changing thesetting of the air flow of the air conditioned air.

A method of controlling a ceiling embedded type air conditioneraccording to a tenth aspect of the present invention is a method ofcontrolling a ceiling embedded type air conditioner embedded in aceiling surface, and comprising an outlet that blows out air conditionedair toward an indoor space, and a guiding means that can change theblow-out vertical direction of the air conditioned air at the outlet,wherein if a state, wherein the guiding means is set so that theblow-out vertical direction of the air conditioned air is oriented to afirst blow-out direction, continues for a first prescribed time orlonger, then the blow-out vertical direction of the air conditioned airis temporarily changed so that it is blown out toward a second blow-outdirection more downward than the first blow-out direction, and theblow-out vertical direction of the air conditioned air is once againchanged so that it blows out in the first blow-out direction.

With this method of controlling a ceiling embedded type air conditioner,if the state, wherein the guiding means provided at the outlet is set sothat the blow-out vertical direction of the air conditioned air is thefirst blow-out direction, continues for the first prescribed time orlonger, then the blow-out vertical direction of the air conditioned airis changed so that the blow-out vertical direction of the airconditioned air is blown out toward the second blow-out direction moredownward than the first blow-out direction; consequently, even if theflow of the air conditioned air blown out from the outlet unfortunatelyclings to the ceiling due to disturbances to the airflow distribution ofthe air conditioned space, such as the opening of a door or window, itis possible to detach that flow from the ceiling surface. Thereby, it ispossible to reduce the time spent in the state wherein the flow of theair conditioned air blown out from the outlet clings to the ceiling, andto reduce staining of the ceiling surface.

Moreover, because the change in the blow-out vertical direction of theair conditioned air to the second blow-out direction is temporary, theblow-out vertical direction of the air conditioned air is changed fromthe first blow-out direction to the second blow-out direction, andsubsequently returned once again so that it blows out toward the firstblow-out direction, the blow-out vertical direction of the airconditioned air can be maximally maintained in the first blow-outdirection set by the user.

BRIEF EXPLANATION OF DRAWINGS

FIG. 1 is an external perspective view of the air conditioner accordingto one embodiment of the present invention.

FIG. 2 is a schematic side cross sectional view of the air conditioner.

FIG. 3 is a plan view of a face panel of the air conditioner viewed fromthe indoor space side.

FIG. 4 is an enlarged view of the vicinity of the outlet.

FIG. 5 is a schematic control block diagram of the air conditioner.

FIG. 6 is a flow chart of ceiling airflow clinging prevention control.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The following explains the embodiments of a ceiling embedded type airconditioner according to the present invention, referencing thedrawings.

(1) Constitution of the Air Conditioner

FIG. 1 is an external perspective view of an air conditioner 1 accordingto one embodiment of the present invention (the ceiling surface is notshown). The air conditioner 1 is a ceiling embedded type air conditionercomprising a casing 2 that internally houses various constituentequipment and a face panel 3 disposed on the lower side of the casing 2.As shown in FIG. 2, the casing 2 is disposed so that it is inserted intoan opening formed in a ceiling surface U of the air conditioned room.Furthermore, the face panel 3 is disposed so that it is fitted into theopening of the ceiling surface U. Here, FIG. 2 is a schematic side crosssectional view of the air conditioner 1.

As shown in FIG. 2, the casing 2 is a box shaped body whose lowersurface is open, and comprises a top plate 21, and a side plate 22extending downward from the circumferential edge part of the top plate21.

As depicted in FIG. 1 and FIG. 3, the face panel 3 is a plate shapedbody fixed to the lower end part of the casing 2 and substantially aquadrilateral in a plan view, and principally comprises at thesubstantial center thereof an inlet 31 that sucks indoor air into thecasing 2, and a plurality (4 in the present embodiment) of outlets 32that blow the air conditioned air from inside the casing 2 out towardthe indoor space. Here, FIG. 3 is a plan view of the face panel 3 of theair conditioner 1 viewed from the indoor space side. The inlet 31 is asubstantially square shaped opening in the present embodiment. Eachoutlet 32 is a substantially rectangular shaped opening that extendselongated along the circumferential edge part of the face panel 3. Theinlet 31 is provided with an inlet grill 33, and a filter 34 foreliminating dust in the indoor air sucked in from the inlet 31.

Inside the casing 2 are principally disposed a fan 4 that sucks theindoor air through the inlet 31 of the face panel 3 into the casing 2and blows it out in the outer circumferential direction, and a heatexchanger 6 disposed so that it surrounds the outer circumference of thefan 4.

The fan 4 is a turbo fan in the present embodiment and comprises a fanmotor 41 provided in the center of the top plate 21 of the casing 2, andan impeller 42 linked to and rotatably driven by the fan motor 41. Theimpeller 42 comprises a disc shaped end plate 43 linked to the fan motor41, a plurality of blades 44 provided at the outer circumferential partof the lower surface of the end plate 43, and a disc shaped end ring 45,which has an opening at its center, provided on the lower side of theblades 44. The fan 4 can suck the indoor air into the interior of theimpeller 42 via the opening of the end ring 45 by the rotation of theblades 44 and can blow it out to the outer circumferential side of theimpeller 42.

In the present embodiment, the heat exchanger 6 is a cross finned tubetype heat exchanger panel formed by bending it so that it surrounds theouter circumference of the fan 4, and is connected via the refrigerantpiping to the outdoor unit (not shown) installed outdoors, and the like.The heat exchanger 6 can function as an evaporator of the refrigerantflowing internally during cooling operation and as a condenser of therefrigerant flowing internally during heating operation. Thereby, theheat exchanger 6 can cool during cooling operation and heat duringheating operation the indoor air that was sucked in through the inlet 31into the casing main body 2 and blown out to the outer circumferentialside of the impeller 42 of the fan 4.

A drain pan 7 is disposed on the lower side of the heat exchanger 6 forreceiving drain water generated by the condensation of moisture in theindoor air when cooling the indoor air in the heat exchanger 6. Thedrain pan 7 is attached to the lower part of the casing main body 2.

In the present embodiment, the drain pan 7 comprises an inlet hole 71formed so that it is in communication with the inlet 31 of the facepanel 3, four outlet holes 72 formed so that they are in communicationwith the outlets 32 of the face panel 3, and a drain water receivinggroove 73 that receives the drain water and is formed on the lower sideof the heat exchanger 6. Furthermore, the inlet hole 71 comprises theinlet 31 of the face panel 3 and an inlet passageway for sucking theindoor air into the casing 2. In addition, each outlet hole 72 comprisesan outlet 32 of the face panel 3 along with an outlet passageway forblowing out into the indoor space the air conditioned air cooled orheated in the heat exchanger 6. In addition, a bell mouth 5 is disposedin the inlet hole 71 of the drain pan 7 for guiding the indoor airsucked in from the inlet 31 to the impeller 42 of the fan 4.

As depicted in FIG. 1 through FIG. 4, each outlet 32 is provided with alouver 35 that serves as a guiding means capable of changing theblow-out vertical direction of the air conditioned air. Here, FIG. 4 isan enlarged view of FIG. 2 and depicts the vicinity of one of theoutlets 32.

In the present embodiment, each louver 35 is a substantially rectangularblade member extending elongated in the longitudinal direction of eachoutlet 32. A linking pin 36 is provided at both end parts of the louver35 in the longitudinal direction, and is supported by the face panel 3so that it is oscillatable about its axis in the longitudinal directionof the outlet 32. Furthermore, adjoining linking pins 36 are mutuallylinked via a linking shaft 37 that serves as a link mechanism. Inaddition, the rotary shaft of a louver motor 38 is linked to one of thelinking shafts 37. Thereby, if the louver motor 38 is driven, then therotation is transmitted from the rotary shaft of the louver motor 38 tothe linking shafts 37, and is further transmitted from the linkingshafts 37 to the linking pins 36, thereby synchronously oscillating allfour louvers 35.

Furthermore, the blow-out vertical direction of the air conditioned airblown from the outlets 32 out into the indoor space can be changed bythe oscillation of the louvers 35. Specifically, the louvers 35 can beset to a swing state by continuously driving the louver motor 38, and toa fixed state that fixes the blow-out vertical direction of the airconditioned air. Namely, if set to the swing state, then louvers 35continuously oscillate and change the blow-out vertical direction of theair conditioned air; additionally, if set to the fixed state, then thelouvers 35 oscillate and are fixed at a desired wind direction positionby the operation of a remote control 84, and the like, which isdiscussed later, and the blow-out vertical direction of the airconditioned air can thereby be set to a fixed direction. In the presentembodiment, the louver motor 38 is a geared motor and is constituted sothat the fixed angle and oscillating range of the louvers 35 can be setin accordance with the energized time of the louver motor 38.

Furthermore, in the present embodiment, the four louvers 35 areconstituted so that they synchronously oscillate by being linked via thelinking shafts 37; however, the present embodiment is not limitedthereto and may be constituted so that each louver 35 oscillatesseparately, for example, if the four louvers 35 were each linked to therotary shaft of a louver motor.

As depicted in FIG. 5, the air conditioner 1 further comprises a controldevice 81 for controlling the speed of the fan 4, the wind directionposition of the louvers 35, and the like. Here, FIG. 5 is a schematiccontrol block diagram of the air conditioner 1.

The control device 81 principally comprises a CPU 82 and a microcomputer comprising memory 83. The control device 81 controls the speedof the fan 4, the wind direction position of the louvers 35, and thelike, by inputting a control signal via the remote control 84, and,based on this signal, executing in the CPU 82 a control program storedin the memory 83, thereby operating the fan motor 41 of the fan 4, thelouver motor 38 of the louvers 35, and the like.

Specifically, in the present embodiment, the wind direction position ofthe louvers 35 in the fixed state can be changed in five stages betweena wind direction position P0 (a first blow-out direction) in thevicinity of the substantially horizontal direction with respect to theceiling surface U and a wind direction position P4 (a second blow-outdirection) more downward than the wind direction position P0 (i.e., thewind direction position P0, a wind direction position P1, a winddirection position P2, a wind direction position P3, and the winddirection position P4), as depicted in FIG. 4. In addition, in thepresent embodiment, the speed of the fan motor 41, i.e., the air volumeof the fan 4, is changeable in three stages: an air volume H wherein thespeed is greatest and the air volume is large; an air volume M whereinthe speed is slightly lower than that of the air volume H and the airvolume is medium; and an air volume L (a second air volume) wherein thespeed is lowest and the air volume is small. Furthermore, the number ofstages that the wind direction position of the louvers 35 and the airvolume of the fan 4 can be changed in the fixed state may be greater orless than the number of stages in which they can be changed as above. Inaddition, the air volume of the fan 4 cannot be set via the remotecontrol 84, but an air volume LL also exists wherein the air volume issmaller than the air volume L and is controllably set in cases such aswhen the air conditioner 1 is in standby operation.

(2) Operation of the Air Conditioner

The basic operation of the air conditioner 1 will first be explained.

When operation starts, the fan motor 41 is driven, rotating the impeller42 of the fan 4. In addition, along with the driving of the fan motor41, refrigerant is supplied from the outdoor unit (not shown) to theinside of the heat exchanger 6. Here, the heat exchanger 6 functions asan evaporator during cooling operation and as a condenser during heatingoperation. Further, attendant with the rotation of the impeller 42, theindoor air is sucked from the inlet 31 of the face panel 3 through thefilter 34 and the bell mouth 5 into the casing 2 from the lower side ofthe fan 4. This sucked in indoor air is blown out to the outercircumferential side by the impeller 42, reaches the heat exchanger 6,is cooled or heated therein, and is then blown through the outlet holes72 and the outlets 32 out toward the indoor space. In so doing, the airconditioned room is cooled or heated.

Incidentally, in a ceiling embedded type air conditioner 1 as in thepresent embodiment, if operation is performed in a state wherein thewind direction position of the louvers 35 is set to a position in thevicinity of substantially the horizontal direction with respect to theceiling surface U, as in the wind direction position P0, then eventssuch as the opening of a door or window, or a room occupant walkingaround, disturb the airflow distribution of the air conditioned space,and a phenomenon (hereinafter, referred to as the ceiling airflowclinging effect) may occur wherein the flow of the air conditioned airblown out from the outlets 32 unfortunately clings to the ceilingsurface U. Accordingly, ceiling airflow clinging prevention controlcapable of preventing such a ceiling airflow clinging effect isincorporated in the control device 81 of the air conditioner 1 of thepresent embodiment.

The following explains the operation of ceiling airflow clingingprevention control, referencing FIG. 6. Here, FIG. 6 is a flow chart ofceiling airflow clinging prevention control. Furthermore, the presentembodiment explains the case of activating ceiling airflow clingingprevention control only in a state wherein the wind direction positionof the louvers 35 is set to the wind direction position P0 (the firstblow-out direction), which is the state that most easily produces thephenomenon in which the flow of the air conditioned air blown out fromthe outlets 32 unfortunately clings to the ceiling surface U.

In step S1, the method judges whether the fan 4 is in operation.

If the fan 4 is in operation, then, in step S2, the method judgeswhether the wind direction position of the louvers 35 is the winddirection position P0.

If the wind direction position of the louvers 35 is the wind directionposition P0, then the method judges in step S3 whether that state hascontinued for a first prescribed (predetermined) time T1 or longer. Atthis time, the method judges whether that state has continued for thefirst prescribed time T1 or longer because if the wind directionposition of the louvers 35 is changed to a wind direction position moredownward than the wind direction position P0, then there is apossibility that there is no ceiling airflow clinging effect. Inaddition, in the present embodiment, the first prescribed time T1 is setto 30 minutes; it is set in this manner because if the time is set toolong, then there is a risk that operation will continue for a longperiod of time in a state wherein the ceiling airflow clinging effect isproduced; in addition, if the time is set too short, then the ceilingairflow clinging effect will tend not to occur, but, as discussed later,the wind direction position of the louvers 35 will be changed moredownwardly than the wind direction position P0, regardless of whetherthe user sets the wind direction position of the louvers 35 to the winddirection position P0; therefore, setting the time empirically toapproximately 30 minutes is appropriate.

Next, if the state wherein the wind direction position of the louvers 35is the wind direction position P0 has continued for the first prescribedtime T1 or longer, then, in step S4, the method judges whether the setair volume (the first air volume) of the fan 4 is equal to or less thanair volume L. Here, the method judges whether the air volume of the fan4 is equal to or less than the air volume L in order to determinewhether control is being executed to lower the air volume of the fan 4for the purpose of not imparting a feeling of a draft to the roomoccupants when changing the wind direction position of the louvers 35downward, as discussed later, and whether the conditions of the set airvolume require such control. Accordingly, in step S4, if the set airvolume of the fan 4 is equal to or less than the air volume L, thensteps S5, S6, which are discussed later, are skipped, and the methodtransitions to step S7.

Next, if the air volume of the fan 4 is greater than the air volume L(e.g., if the set air volume is the air volume M or the air volume H),then, in step S5, an instruction is issued to change the air volume ofthe fan 4 to the air volume L (the second air volume). Thereby, the airvolume of the fan 4 can, in advance, begin to be reduced to the airvolume L prior to performing control that changes the wind directionposition of the louvers 35 downward, which is discussed later. Here, theair volume L is the lower limit of the air volume of the fan 4 settableby the user via the remote control 84, and is the air volume that tendsnot to impart a feeling of a draft to the room occupants.

Furthermore, after the instruction to change the air volume of the fan 4to the air volume L, in step S6, the method judges whether a secondprescribed (predetermined) time T2 has elapsed. At this point, themethod judges whether the second prescribed time T2 has elapsed sincethe instruction in order to wait for the air volume of the fan 4 totransition to the air volume L. In addition, in the present embodiment,the second prescribed time T2 is set to 10 seconds; however, it is setin this manner in order to take into consideration, in a case whereinthe air volume of the fan 4 is reduced to the air volume L from a statewherein the air volume of the fan 4 is the air volume H, which is themaximum air volume, the time from when the instruction to change thatair volume was executed to the time when the speed of the fan 4decreased to the air volume L. Consequently, after the instruction tochange the air volume of the fan 4 to the air volume L, the air volumeof the fan 4 is reliably reduced to the air volume L after the secondprescribed time T2 has elapsed.

Next, if the second prescribed time T2 has elapsed, then, in step S7,the wind direction position of the louvers 35 is set to the winddirection position P4 (the second blow-out direction). In so doing, evenif operation is performed in the state wherein the wind directionposition of the louvers 35 is set to the wind direction position P0 andthe ceiling airflow clinging effect arises, the flow of the airconditioned air blown out from the outlets 32 can be guided downward anddetached from the ceiling surface U. Thereby, the time during which theceiling airflow clinging effect is produced can be automatically reducedwithout manual operation by the user, and staining of the ceilingsurface U can be reduced. Here, the wind direction position P4 is thelower limit of the wind direction position of the louvers 35 that can beset by the user via the remote control 84, and is the wind directionposition at which the flow of the air conditioned air that produces theceiling airflow clinging effect can be detached from the ceiling surfaceU.

Moreover, in steps S5, S6, the air volume of the fan 4 is reducedbeforehand to the air volume L, and a feeling of a draft is not impartedto the room occupants when the wind direction position of the louvers 35is changed from the wind direction position P0 to the wind directionposition P4.

Furthermore, if the wind direction position of the louvers 35 is changedto the wind direction position P4, then, in step S8, the wind directionposition of the louvers 35 is once again changed to the wind directionposition P0 (the first blow-out direction). In other words, the winddirection position of the louvers 35 is temporarily changed in step S7from the wind direction position P0 to the wind direction position P4,then returned once again to the wind direction position P0, therebyminimizing the time in which the air conditioned air blown out from theoutlets 32 is blown out in a state wherein the wind direction positionof the louvers 35 is the wind direction position P4. Consequently, theceiling airflow clinging effect can be prevented while maximallymaintaining the wind direction position of the louvers 35 set by theuser at the wind direction position P0.

Next, after the wind direction position of the louvers 35 is changedfrom the wind direction position P4 to the wind direction position P0,in step S9, the air volume of the fan 4 is changed from the air volume Lto the set air volume (the first air volume) for the case when the winddirection position of the louvers 35 is the wind direction position P0.In other words, the air volume of the fan 4 is changed to the air volumeL prior to the wind direction position of the louvers 35 being changedtemporarily from the wind direction position P0 to the wind directionposition P4 in steps S5, S6, and is then changed once again to the setair volume (e.g., the air volume M or the air volume H) for the casewhen the wind direction position of the louvers 35 is the wind directionposition P0, after the wind direction position of the louvers 35 isreturned from the wind direction position P4 to the wind directionposition P0; therefore, the air volume of the fan 4 does not increaseduring the time from the wind direction position P4 until returned tothe wind direction position P0. Consequently, a feeling of a draft isnot imparted to the room occupants.

Furthermore, if the set air volume of the fan 4 is the air volume L whenthe wind direction position of the louvers 35 is the wind directionposition P0, then, in step S9, it is perfunctory set from the air volumeL to the air volume L, but the air volume of the fan 4 does not changesubstantially.

The following explains the process for the case wherein the user haschanged the setting of the wind direction position of the louvers 35 viathe remote control 84 when the process from step S4 to step S9 is beingperformed. For example, if an instruction is given to change the settingto the wind direction position of the louvers 35 to the wind directionposition P2 (a third blow-out direction) in the middle of executingcontrol in step S7 to change the wind direction position of the louvers35 from the wind direction position P0 (the first blow-out direction) tothe wind direction position P4 (the second blow-out direction), thenprocessing can be performed so that control to change the wind directionposition of the louvers 35 from the wind direction position P0 to thewind direction position P4 is performed as is, and the wind directionposition of the louvers 35 is changed in step S8 from the wind directionposition P4 to the wind direction position P2 without changing it fromthe wind direction position P4 to the wind direction position P0.

In other words, even if an instruction were given to change the settingof the wind direction position of the louvers 35 during the time whenthe wind direction position of the louvers 35 is temporarily changedfrom the wind direction position P0 to the wind direction position P4and then once again changed from the wind direction position P4 to thewind direction position P0, then it would go through the process ofchanging from the wind direction position P0 to the wind directionposition P4; consequently, even if operation were performed in a statewherein the wind direction position of the louvers 35 was set to thewind direction position P0 and the ceiling airflow clinging effectarose, the flow of the air conditioned air blown out from the outlets 32could be guided downward and detached from the ceiling surface U.

Moreover, after the wind direction position of the louvers 35 is changedfrom the wind direction position P0 to the wind direction position P4,the wind direction position of the louvers 35 is directly changed fromthe wind direction position P4 to the wind direction position P2 withoutchanging from the wind direction position P4 to the wind directionposition P0, and the responsiveness to changing the setting of the winddirection position of the louvers 35 can thereby be improved.

In addition, even if the user changes the setting of the air volume ofthe fan 4 via the remote control 84 when the process from step S4 tostep S9 is being performed, a process the same as the abovementionedprocess is performed for the case wherein the setting of the winddirection position of the louvers 35 has changed. For example, if aninstruction is issued to change the setting of the air volume of the fan4 to the air volume M (a third air volume) in the middle of executingcontrol in steps S5, S6 to change the air volume of the fan 4 from theset air volume (the first air volume, e.g., the air volume H), with thewind direction position of the louvers 35 at the wind direction positionP0, to the air volume L (the second air volume), then processing can beexecuted so that the control to change the air volume of the fan 4 fromthe air volume H to the air volume L is performed as is, and the settingof the air volume of the fan 4 is changed from the air volume L to theair volume M without changing it from the air volume L to the air volumeH.

In other words, even if an instruction is given to change the setting ofthe air volume of the fan 4 during the time when the wind directionposition of the louvers 35 is temporarily changed from the winddirection position P0 to the wind direction position P4 and then onceagain changed from the wind direction position P4 to the wind directionposition P0, then it goes through the process of changing the air volumeof the fan 4 from the air volume H to the air volume L; consequently, afeeling of a draft is reliably not imparted to the room occupants.

Moreover, because the air volume of the fan 4 is changed from the airvolume H to the air volume L and then directly changed from the airvolume L to the air volume M without changing from the air volume L tothe air volume H, the responsiveness to changing the setting of the airvolume of the fan 4 can be improved.

Thus, even if the user changes the setting of the wind directionposition of the louvers 35 or the air volume of the fan 4 via the remotecontrol 84 when the process from step S4 to step S9 is being performed,it is possible to perform operation that guides the flow of the airconditioned air blown out from the outlets 32 downward and detaches itfrom the ceiling surface U, and to perform operation that reduces theair volume of the fan 4 so that a feeling of a draft is not imparted tothe room occupants.

(3) Other Embodiments

The above explained an embodiment of the present invention based on thedrawings, but the specific constitution is not limited to theseembodiments, and it is understood that variations and modifications maybe effected without departing from the spirit and scope of theinvention.

(A)

In the abovementioned embodiment, when changing the wind directionposition of the louvers 35 from the wind direction position P0 to thewind direction position P4, the air volume is changed in steps S4, S5 tothe air volume L, which is the lower limit of the air volume that can beset by the user via the remote control 84; however, if the airconditioner 1 is in standby operation and the like, then it may bechanged to the air volume LL, which is an air volume smaller than theair volume L that is controllably set.

(B)

In the abovementioned embodiment, after an instruction that changes theair volume of the fan 4, the method waits for the elapse of the secondprescribed time T2 in step S6; however, if the response to the speedcontrol of the fan 4 is fast, then the step S6 may be omitted because itis not necessary to wait for the elapse of the second prescribed timeT2.

(C)

In the abovementioned embodiment, the condition of the wind directionposition of the louvers 35 that activates ceiling airflow clingingprevention control was set only for the case wherein the wind directionposition P0 state continued for the first prescribed time or longer;however, to further reliably prevent the ceiling airflow clingingeffect, the condition may also be set for the case wherein the winddirection positions P0 and P1 states continue for the first prescribedtime or longer.

(D)

In the abovementioned embodiment, the wind direction position of thelouvers 35 is changed in step S7 from the wind direction position P0downward to the wind direction position P4; however, if the ceilingairflow clinging effect can be prevented, then it may be changed fromthe wind direction position P0 downward to the wind direction positionP3, which is upward of the wind direction position P4.

(E)

In the abovementioned embodiment, the present embodiment was applied toa four directional blow-out type ceiling embedded type air conditioner,but may also be applied to other ceiling embedded type air conditioners,such as a two directional blow-out type.

Industrial Field of Application

By using the present invention, it is possible with a ceiling embeddedtype air conditioner to prevent the unfortunate clinging to the ceilingsurface of the flow of the air conditioned air blown out from theoutlets due to disturbances to the airflow distribution of the airconditioned space, such as the opening of a door or window.

What is claimed is:
 1. A ceiling embedded type air conditionercomprising: a casing housing the air conditioner being embedded in aceiling; an outlet configured to blow out air conditioned air toward anindoor space; a guiding member movably mounted with respect to saidcasing to change a blow-out vertical direction of the air conditionedair at said outlet; and a control device operatively controlling saidguiding member between a plurality of fixed positions tier changing saidblow-out vertical direction of the air conditioned air blown out fromsaid outlet to said indoor space, said plurality of fixed positionsincluding at least a first blow-out direction, a second blow-outdirection and a third blow-out direction, said control device configuredto perform a ceiling airflow clinging prevention control operation inwhich said control device gives a temporary blow-out direction changinginstruction to said guiding member that temporarily changes saidblow-out vertical direction of the air conditioned air from said firstblow-out direction to said second blow-out direction only afterdetermining said guide member has been in said first blow-out directionfor a first predetermined time or longer, said second blow-out directionbeing a direction corresponding to one of said fixed positions at whichsaid guiding member is more downward than said first blow-out direction,said first blow-out direction being a direction corresponding to anupper limit of said fixed positions at which said guiding member changessaid blow-out vertical direction of the air conditioned air blown outfrom said outlet to said indoor space, said third blow-out directionbeing a direction corresponding to one of said fixed positions at whichsaid blow-out vertical direction of the air conditioned air from saidguiding member is between said first and second blow-out directions,said control device being further configured and arranged to give saidtemporary blow-out direction changing instruction based only on anamount of time said guide member has been in said first blow-outdirection when said ceiling airflow clinging prevention controloperation is performed, and said control device giving a blow-outdirection user setting instruction to said guiding member to change fromsaid second blow-out direction to said third blow-out direction withoutchanging to said first blow-out direction in response to a user inputcommand after said guiding member has temporarily changed said blow-outvertical direction of the air conditioned air from said first blow-outdirection to said second blow-out direction, when said blow-outdirection user setting instruction is given during a time when theblow-out vertical direction of the air conditioned air is in a processof being temporarily changed by said temporary blow-out directionchanging instruction from said first blow-out direction to said secondblow-out direction.
 2. The ceiling embedded type air conditioner asrecited in claim 1, wherein said second blow-out direction is adirection corresponding to a lower limit at which said guiding memberchanges said blow-out vertical direction of the air conditioned airblown out from said outlet to said indoor space.
 3. The ceiling embeddedtype air conditioner as recited in claim 1, further comprising a fanbeing configured to suck in and blow out air, said control devicefurther giving a temporary air volume changing instruction to said fanin response to said control device determining the guide member has beenin said first blow-out direction for the first predetermined time orlonger, said temporary air volume changing instruction temporarilychanging an air volume of the air conditioned air from a first airvolume to a second air volume that is smaller than said first air volumeprior to said guide member being changed from said first blow-outdirection to said second blow-out direction in response to said controldevice determining said guide member has been in said first blow-outdirection for the first predetermined time or longer, and said controldevice further giving additional instructions to said guiding memberthat changes said blow-out vertical direction of the air conditioned airfrom said second blow-out direction to said first blow-out direction,and to the fan that changes the air volume of the air conditioned airfrom said second air volume to said first air volume in response to saidguiding member reaching said first blow-out direction by executing saidtemporary blow-out direction changing instruction.
 4. The ceilingembedded type air conditioner as recited in claim 3, wherein said secondair volume corresponds to a lower limit of a variable air volume rangeof said air conditioned air.
 5. The ceiling embedded air conditioner asrecited in claim 3, wherein said control device gives an air volume usersetting instruction to said fan to change the air volume of the airconditioned air from said second air volume to a third air volumewithout changing to said first air volume in response to a user inputcommand after said fan has temporarily changed the air volume of the airconditioned air from said first air volume to said second air volume,when said air volume user setting instruction is given during a timewhen the blow-out vertical direction of the air conditioned air is in aprocess of being temporarily changed by said temporary blow-outdirection changing instruction from said first blow-out direction tosaid second blow-out direction.
 6. The ceiling embedded type airconditioner as recited in claim 3, wherein said first blow-out directionis a direction corresponding to an upper limit at which said guidingmember changes said blow-out vertical direction of the air conditionedair blown out from said outlet to said indoor space.
 7. The ceilingembedded type air conditioner as recited in claim 3, wherein said secondblow-out direction is a direction corresponding to a lower limit atwhich said guiding member changes said blow-out vertical direction ofthe air conditioned air blown out from said outlet to said indoor space.8. The ceiling embedded type air conditioner as recited in claim 3,wherein said control device gives a blow-out direction user settinginstruction to said guiding member to change from said second blow-outdirection to said third blow-out direction without changing to saidfirst blow-out direction in response to a user input command after saidguiding member has temporarily changed said blow-out vertical directionof the air conditioned air from said first blow-out direction to saidsecond blow-out direction, when said blow-out direction user settinginstruction is given during a time when the blow-out vertical directionof the air conditioned air is in a process of being temporarily changedby said temporary blow-out direction changing instruction from saidfirst blow-out direction to said second blow-out direction.
 9. A ceilingembedded type air conditioner, comprising: a casing housing the airconditioner being embedded in a ceiling; a fan being configured to suckin and blow out air; an outlet configured to blow out air conditionedair toward an indoor space; and a guiding member movably mounted withrespect to said casing to change a blow-out vertical direction of theair conditioned air at said outlet; and a control device operativelycontrolling said guiding member between a plurality of fixed positionsfor changing said blow-out vertical direction of the air conditioned airblown out from said outlet to said indoor space, said plurality of fixedpositions including at least first blow-out direction and a secondblow-out direction, said control device configured to perform a ceilingairflow clinging prevention control operation in which said controldevice gives a temporary air volume changing instruction to said fanthat temporarily changes an air volume of the air conditioned air from afirst air volume to a second air volume that is smaller than said firstair volume after determining said guide member has been in said firstblow-out direction for a first predetermined time or longer, said secondblow-out direction being a direction corresponding to one of said fixedpositions at which said guiding member is more downward than said firstblow-out direction, said control device giving a temporary blow-outdirection changing instruction to said guiding member that changes theblow-out vertical direction of the air conditioned air from said firstblow-out direction to said second blow-out direction after saidtemporary air volume changing instruction to said fan is given by saidcontrol device to change said air volume from said first air volume tosaid second air volume and a second predetermined time has elapsed sincegiving said temporary air volume changing instruction when said ceilingairflow clinging prevention control operation is performed, and saidcontrol device giving a blow-out direction user setting instruction tosaid guiding member to change from said second blow-out direction tosaid third blow-out direction without changing to said first blow-outdirection in response to a user input command after said guiding memberhas temporarily changed said blow-out vertical direction of the airconditioned air from said first blow-out direction to said secondblow-out direction, when said blow-out direction user settinginstruction is given during a time when the blow-out vertical directionof the air conditioned air is in a process of being temporarily changedby said temporary blow-out direction changing instruction from saidfirst blow-out direction to said second blow-out direction.
 10. Theceiling embedded type air conditioner as recited in claim 9, whereinsaid second air volume corresponds to a lower limit of a variable airvolume range of said air conditioned air.
 11. The ceiling embedded typeair conditioner as recited in claim 9, wherein said control device givesan air volume user setting instruction to said fan to change the airvolume of the air conditioned air from said second air volume to a thirdair volume without changing to said first air volume in response to auser input command after said fan has temporarily changed the air volumeof the air conditioned air from said first air volume to said second airvolume, when said air volume user setting instruction is given during atime when the blow-out vertical direction of the air conditioned air isin a process of being temporarily changed by said temporary blow-outdirection changing instruction from said first blow-out direction tosaid second blow-out direction.
 12. The ceiling embedded type airconditioner as recited in claim 9, wherein said first blow-out directionis a direction corresponding to an upper limit at which said guidingmember changes said blow-out vertical direction of the air conditionedair blown out from said outlet to said indoor space.
 13. The ceilingtype air conditioner as recited in claim 9, wherein said second blow-outdirection is a direction corresponding to a lower limit at which saidguiding member changes said blow-out vertical direction of the airconditioned air blown out from said outlet to said indoor space.
 14. Theceiling embedded type air conditioner as recited in claim 9, whereinsaid control device further gives a subsequent air volume changinginstruction to said fan to change the air volume of the air conditionedair from said second air volume to said first air volume after saidblow-out vertical direction of the air conditioned air has been changedby said guiding member from said second blow-out direction to said firstblow-out direction.
 15. The ceiling embedded type air conditioner asrecited in claim 14, wherein said second air volume corresponds to alower limit of a variable air volume range of said air conditioned air.16. The ceiling embedded type air conditioner as recited in claim 14,wherein said control device gives an air volume user setting instructionto said fan to change the air volume of the air conditioned air fromsaid second air volume to a third air volume without changing to saidfirst air volume in response to a user input command after said fan hastemporarily changed the air volume of the air conditioned air from saidfirst air volume to said second air volume, when said air volume usersetting instruction is given during a time when the blow-out verticaldirection of the air conditioned air is in a process of beingtemporarily changed by said temporary blow-out direction changinginstruction from said first blow-out direction to said second blow-outdirection.
 17. A method of controlling a ceiling embedded type airconditioner embedded in a ceiling surface comprising: selectivelycontrolling movement of a guiding member with respect to a casing of theair conditioner that is embedded in the ceiling surface between aplurality of fixed positions for changing a blow-out vertical directionof air conditioned air blown out from an outlet to an indoor space; andselectively controlling an air volume of a fan that blows out air viasaid outlet between a first air volume and a second air volume that islower than said first air volume, said controlling of the movement ofsaid guiding member including performing a ceiling airflow clingingprevention control operation in which said guiding member is set tochange the blow-out vertical direction of the air conditioned air from afirst blow-out direction to a second blow-out direction upon determiningthe air conditioned air is at said second air volume for a firstpredetermined time or longer, said second blow-out direction being moredownward than said first blow-out direction, said controlling of the airvolume of said fan when performing said ceiling airflow clingingprevention control operation including changing said air volume of theair conditioned air from said first air volume to said second air volumeif the air conditioned air is at said first air volume and delaying saidsetting of said guiding member from said first blow-out direction tosaid second blow-out direction until after a second predetermined timehas elapsed since said changing said first air volume to said second airvolume, said controlling of the movement of said guiding member whenperforming said ceiling airflow clinging prevention control operationincluding changing the blow-out vertical direction of the airconditioned air back to said first blow-out direction from said secondblow-out direction, said controlling of the air volume of said fan whenperforming said ceiling airflow clinging prevention control operationincluding changing said air volume of the air conditioned air from saidsecond air volume to said first air volume after the changing of theblow-out vertical direction of the air conditioned air back to saidfirst blow-out direction from said second blow-out direction, and saidcontrolling of the movement of said guiding member including giving ablow-out direction user setting instruction to said guiding member tochange from said second blow-out direction to said third blow-outdirection without changing to said first blow-out direction in responseto a user input command after said guiding member has temporarilychanged said blow-out vertical direction of the air conditioned air fromsaid first blow-out direction to said second blow-out direction, whensaid blow-out direction user setting instruction is given during a timewhen the blow-out vertical direction of the air conditioned air is inprocess of being temporarily changed by said temporary blow-outdirection changing instruction from said first blow-out direction tosaid second blow-out direction.
 18. A method of controlling a ceilingembedded type air conditioner embedded in a ceiling surface comprising:selectively controlling movement of a guiding member with respect to acasing of the air conditioner that is embedded in the ceiling surfacebetween a plurality of fixed positions for changing a blow-out verticaldirection of the air conditioned air blown out from an outlet to anindoor space, said plurality of fixed positions including at least afirst blow-out direction, a second blow-out direction and a thirdblow-out direction, with said third blow-out direction being a directioncorresponding to one of said fixed positions at which said blow-outvertical direction of the air conditioned air from said guiding memberis between said first and second blow-out directions; and selectivelycontrolling an air volume of a fan that blows out air via said outletbetween a first air volume and a second air volume that is lower thansaid first air volume, said controlling of the movement of said guidingmember including performing a ceiling airflow clinging preventioncontrol operation in which a temporary blow-out direction changinginstruction. is given to said guiding member to change the blow-outvertical direction of the air conditioned air from a first blow-outdirection to a second blow-out direction only after determining saidguide member has been in said first blow-out direction for a firstpredetermined time or longer, said second blow-out direction being adirection corresponding to one of said fixed positions at which saidguiding member is more downward than said first blow-out direction, saidfirst blow-out direction being a direction corresponding to an upperlimit of said fixed positions at which said guiding member changes saidblow-out vertical direction of the air conditioned air blown out fromsaid outlet to said indoor space, said controlling of the movement ofsaid guiding member when performing said ceiling airflow clingingprevention control operation including changing the blow-out verticaldirection of the air conditioned air back to said first blow-outdirection from said second blow-out direction, giving said temporaryblow-out direction changing instruction. being based only on an amountof time said guide member has been in said first blow-oft direction whensaid ceiling airflow clinging prevention control operation is performed,and said controlling of the movement of said guiding member includinggiving a blow-out direction user setting instruction to said guidingmember to change from said second blow-out direction to said thirdblow-out direction without changing to said first blow-out direction inresponse to a user input command after said guiding member hastemporarily changed said blow-out vertical direction of the airconditioned air from said first blow-out direction to said secondblow-out direction, when said blow-out direction user settinginstruction is given during a time when the blow-out vertical directionof the air conditioned air is in a process of being temporarily changedb said temporary blow-out direction changing instruction from said firstblow-out direction to said second blow-out direction.